Looking at this Nest question reminded me that I'd really want one of these for my future house. The Nest website says that it's currently only available in the US but I'm wondering whether that is just a sales/marketing choice of if there might be technical reasons for the US limitation.

The Nest website has a widget where you can tick what cables you've got and it then tells you whether the Nest will work with that. I'm not sure that these cable markings/colors are international though. I would get a Vaillant gas heater very similar to this one.

At $250 it's just expensive enough that I hesitate to just order one and try if it works. Even if I did, I would also be afraid of damaging it by connecting the wires wrong.

Do the markings/colors on cables of gas heaters/thermostats follow an international standard?

Can I expect that a Nest would work in Europe, when connected to a European brand model?

I love the design of NEST, but I haven't been able to justify the cost. Given a programmable thermostat runs in the $50 range, and once set, you really don't touch it more than maybe once or twice a year, $250 seems excessive.
– DA01Apr 12 '12 at 13:37

They announced yesterday that there is availability in other countries now.
– StevenMay 30 '12 at 19:32

Canada qualifies as other countries but that's it, as far as I can tell. The website explicitly says Europe not yet, anyway.
– Torben Gundtofte-BruunMay 30 '12 at 19:45

5 Answers
5

One big thing to remember about Nest is that it is a low voltage thermostat. Therefore, it can't be used on a typical heating system in the UK (say) as we tend to have 240V connections to thermostats and timers.

Check the voltage of your existing thermostat/timer. If it's a low voltage one then Nest should work.

Actually, you should be able to make them work in the UK. An electrically savvy friend of mine has one up for sale on ebay along with this note:

I would suggest that only the technology savvy avid DIYer, or keen professional electrician with enough research install this item. Unfortunately because this thermostat is not intended for direct installation to common UK Central Heating systems, I will not accept returns. It can be installed though! It will work just fine when correctly installed, but there are the following caveats:

The Nest thermostat works on 24V AC North American HVAC wiring - in the UK most commonly we have zero volt contacts for Thermostats. You can easily make this work with a 24V AC power supply and a relay after carefully studying the wiring. The Nest draws a tiny current (12mA) through the coil to trickle charge its internal battery so I would suggest a good sized relay to avoid buzzing.

The WiFi in the Nest can only handle US FCC approved channels 1-11. In the UK we allow channels 1-13, so just make sure your wireless access point is not set to channel 12 or 13. No big deal.

You must skip the 'enter your zip code' stage of the setup process. The Nest will not access weather data outside of the USA. The smart algorithms still work fine without weather data - the sensors to check the temperature inside your house is what is most important anyway.

The Nest iPhone and Android apps to control your temperature from your phone are not available outside of the US. If you have a rooted Android phone, you can install 'Market Enabler' to install the Nest app from the US Market and then it should work just fine. I have no idea about whether such a thing is possible for the iOS App Store.

Once those four things are paid attention to, it should work well! Would be a fantastic, high quality, high tech, rare addition to your home and definitely a cool talking point.

Thank you for more or less proving that it can be done!! Oh boy I would love to do this, but I'm not so keen on hacking around with heating stuff in a new house. I've still accepted another answer because this one (although technically enticing) would not be recommendable to the average person. Also, the Apple App Store requires a US credit card to access US apps; I'm not aware of any hack to circumvent that and it would be a pity to have the Nest without the app.
– Torben Gundtofte-BruunMar 1 '12 at 20:43

1

No worries. @ChrisF's answer is right for the vast majority of folks. I just popped this up here as a technically challenging alternative :-)
– Rory AlsopMar 1 '12 at 21:29

You can create US App Store account without a credit card. You just need an email address not currently tied to an Apple ID. Lots of instructions are available if you goggle it. You can use this account to download the free apps only available in the US.
– pddMay 30 '12 at 3:47

As stated in latest software update (version 4.0) release notes, now you can input an European zip code! Nest will handle that correctly!
– ermannobNov 16 '13 at 17:12

Here are other personal experiences with using this device in The Nederlands.

Below a list of problems I encountered with the product due to the
fact I’m not living in the US:

You can only set time by entering a US zipcode. No time support for timezones outside the US. How difficult can it be to make a basic
functionality like a clock work all around the globe? There is no
option to set the time or timezone manually.

Weather is only available for US cities. This is actually related to the point above. The location for weather can only be
set with the zipcode. It is not possible to disable weather at all.
How difficult would it be to make weather work globally, or to make
it possible to disable it? Most weather databases work globally
anyway.

No 24h clock support. Why not? That’s a simple switch? Setting the temperature to Celsius is possible though, while Fahrenheit is
the only system used in the US. iPhone/iPad app is only available
from the US appstore.This is just checking a checkbox in Itunes
Producer.

Auto away only works when Nest thinks it’s daytime. I managed to kinda work around the timezone issue by setting it to Honolulu,
which is exactly a 12 hour difference with the Nerherlands. So
during the night in my place the Nest thinks it’s day and vice
versa. I saw that auto away only works during daytime, so in my
case nighttime. This caused my heater to stop working until I
activated it by entering the room again. So no preheated room for
me in the morning. I had to disable auto away. This also seems a
problem for people who work at night in the US.

No OpenTherm support. OpenTherm is a widely used system for modulating heaters. Ok, it’s a non-US system, so I can accept that,
since it’s indeed only sold in the US, but still I’m missing this
feature.

Build quality is dissapointing. One of the unique selling points used to promote the product is that it is designed by a former
Apple designer. While this might be true it’s not a very solid
product. The ring that you use to control it with doesn’t run
freely. It makes a scraping sound when you turn it sometimes. It is
very sensitive too, so if you want to set a temperature in the
schedule and press the ring to confirm it, most times by pressing
you also change your setting slightly. Build quality is ok for a
product like this, but expectations are higher when the name
“Apple” is mentioned.

I believe the reason that they say US only is because they provide services over the internet for which they only have US data. I have a Filtrete Wi-Fi thermostat the has the same disclaimer, but it works just fine in Canada and their software even correctly displays Canadian weather.

As for the wires, there is not really a "standard" but instead a general pattern; but don't just assume this is followed. Make sure to mark the cables based on how they are connected to your existing thermostat. It's not uncommon for people to deviate. You will also require a C (common) wire for this hookup - you may or may not already have this, but if you don't, you will need to run an additional conductor back to your furnace.

In The Netherlands, most systems use the same 24v system as in the US, so the Nest powered up nicely. It works fine, but I haven't connected it to the Internet - so I cannot control it remotely or use the apps to see savings and so on.

For me it was not possible to skip the zip-code question, it would not go further without the zip-code. So I entered 00000 as a zipcode. The main problem is that it uses the zipcode to determine the date and time - so it adjusts its time to a US timezone!!! Only when not connected to the Internet you can enter the time manually. When you connect again it will re-adjust its time.

If you are in the wrong timezone reading the shedule is really a hassle - even if you manage to find a zone that differs exactly 12hrs.

So besides technical challenges you will also have to live either with no connectivity or a wrong timezone.

Thank you for your interest in this question.
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